// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_GFX_GEOMETRY_RECT_F_H_
#define UI_GFX_GEOMETRY_RECT_F_H_

#include <iosfwd>
#include <string>

#include "build/build_config.h"
#include "ui/gfx/geometry/point_f.h"
#include "ui/gfx/geometry/rect.h"
#include "ui/gfx/geometry/size_f.h"
#include "ui/gfx/geometry/vector2d_f.h"

#if defined(OS_MACOSX)
typedef struct CGRect CGRect;
#endif

namespace gfx {

class InsetsF;

// A floating version of gfx::Rect.
class GFX_EXPORT RectF {
public:
    RectF() { }
    RectF(float width, float height)
        : size_(width, height)
    {
    }
    RectF(float x, float y, float width, float height)
        : origin_(x, y)
        , size_(width, height)
    {
    }
    explicit RectF(const SizeF& size)
        : size_(size)
    {
    }
    RectF(const PointF& origin, const SizeF& size)
        : origin_(origin)
        , size_(size)
    {
    }

    explicit RectF(const Rect& r)
        : RectF(static_cast<float>(r.x()),
            static_cast<float>(r.y()),
            static_cast<float>(r.width()),
            static_cast<float>(r.height()))
    {
    }

#if defined(OS_MACOSX)
    explicit RectF(const CGRect& r);
    // Construct an equivalent CoreGraphics object.
    CGRect ToCGRect() const;
#endif

    ~RectF()
    {
    }

    float x() const { return origin_.x(); }
    void set_x(float x) { origin_.set_x(x); }

    float y() const { return origin_.y(); }
    void set_y(float y) { origin_.set_y(y); }

    float width() const { return size_.width(); }
    void set_width(float width) { size_.set_width(width); }

    float height() const { return size_.height(); }
    void set_height(float height) { size_.set_height(height); }

    const PointF& origin() const { return origin_; }
    void set_origin(const PointF& origin) { origin_ = origin; }

    const SizeF& size() const { return size_; }
    void set_size(const SizeF& size) { size_ = size; }

    float right() const { return x() + width(); }
    float bottom() const { return y() + height(); }

    PointF top_right() const { return PointF(right(), y()); }
    PointF bottom_left() const { return PointF(x(), bottom()); }
    PointF bottom_right() const { return PointF(right(), bottom()); }

    Vector2dF OffsetFromOrigin() const { return Vector2dF(x(), y()); }

    void SetRect(float x, float y, float width, float height)
    {
        origin_.SetPoint(x, y);
        size_.SetSize(width, height);
    }

    // Shrink the rectangle by a horizontal and vertical distance on all sides.
    void Inset(float horizontal, float vertical)
    {
        Inset(horizontal, vertical, horizontal, vertical);
    }

    // Shrink the rectangle by the given insets.
    void Inset(const InsetsF& insets);

    // Shrink the rectangle by the specified amount on each side.
    void Inset(float left, float top, float right, float bottom);

    // Move the rectangle by a horizontal and vertical distance.
    void Offset(float horizontal, float vertical);
    void Offset(const Vector2dF& distance) { Offset(distance.x(), distance.y()); }
    void operator+=(const Vector2dF& offset);
    void operator-=(const Vector2dF& offset);

    InsetsF InsetsFrom(const RectF& inner) const;

    // Returns true if the area of the rectangle is zero.
    bool IsEmpty() const { return size_.IsEmpty(); }

    // A rect is less than another rect if its origin is less than
    // the other rect's origin. If the origins are equal, then the
    // shortest rect is less than the other. If the origin and the
    // height are equal, then the narrowest rect is less than.
    // This comparison is required to use Rects in sets, or sorted
    // vectors.
    bool operator<(const RectF& other) const;

    // Returns true if the point identified by point_x and point_y falls inside
    // this rectangle.  The point (x, y) is inside the rectangle, but the
    // point (x + width, y + height) is not.
    bool Contains(float point_x, float point_y) const;

    // Returns true if the specified point is contained by this rectangle.
    bool Contains(const PointF& point) const
    {
        return Contains(point.x(), point.y());
    }

    // Returns true if this rectangle contains the specified rectangle.
    bool Contains(const RectF& rect) const;

    // Returns true if this rectangle intersects the specified rectangle.
    // An empty rectangle doesn't intersect any rectangle.
    bool Intersects(const RectF& rect) const;

    // Computes the intersection of this rectangle with the given rectangle.
    void Intersect(const RectF& rect);

    // Computes the union of this rectangle with the given rectangle.  The union
    // is the smallest rectangle containing both rectangles.
    void Union(const RectF& rect);

    // Computes the rectangle resulting from subtracting |rect| from |*this|,
    // i.e. the bounding rect of |Region(*this) - Region(rect)|.
    void Subtract(const RectF& rect);

    // Fits as much of the receiving rectangle into the supplied rectangle as
    // possible, becoming the result. For example, if the receiver had
    // a x-location of 2 and a width of 4, and the supplied rectangle had
    // an x-location of 0 with a width of 5, the returned rectangle would have
    // an x-location of 1 with a width of 4.
    void AdjustToFit(const RectF& rect);

    // Returns the center of this rectangle.
    PointF CenterPoint() const;

    // Becomes a rectangle that has the same center point but with a size capped
    // at given |size|.
    void ClampToCenteredSize(const SizeF& size);

    // Splits |this| in two halves, |left_half| and |right_half|.
    void SplitVertically(RectF* left_half, RectF* right_half) const;

    // Returns true if this rectangle shares an entire edge (i.e., same width or
    // same height) with the given rectangle, and the rectangles do not overlap.
    bool SharesEdgeWith(const RectF& rect) const;

    // Returns the manhattan distance from the rect to the point. If the point is
    // inside the rect, returns 0.
    float ManhattanDistanceToPoint(const PointF& point) const;

    // Returns the manhattan distance between the contents of this rect and the
    // contents of the given rect. That is, if the intersection of the two rects
    // is non-empty then the function returns 0. If the rects share a side, it
    // returns the smallest non-zero value appropriate for float.
    float ManhattanInternalDistance(const RectF& rect) const;

    // Scales the rectangle by |scale|.
    void Scale(float scale)
    {
        Scale(scale, scale);
    }

    void Scale(float x_scale, float y_scale)
    {
        set_origin(ScalePoint(origin(), x_scale, y_scale));
        set_size(ScaleSize(size(), x_scale, y_scale));
    }

    // This method reports if the RectF can be safely converted to an integer
    // Rect. When it is false, some dimension of the RectF is outside the bounds
    // of what an integer can represent, and converting it to a Rect will require
    // clamping.
    bool IsExpressibleAsRect() const;

    std::string ToString() const;

private:
    PointF origin_;
    SizeF size_;
};

inline bool operator==(const RectF& lhs, const RectF& rhs)
{
    return lhs.origin() == rhs.origin() && lhs.size() == rhs.size();
}

inline bool operator!=(const RectF& lhs, const RectF& rhs)
{
    return !(lhs == rhs);
}

inline RectF operator+(const RectF& lhs, const Vector2dF& rhs)
{
    return RectF(lhs.x() + rhs.x(), lhs.y() + rhs.y(),
        lhs.width(), lhs.height());
}

inline RectF operator-(const RectF& lhs, const Vector2dF& rhs)
{
    return RectF(lhs.x() - rhs.x(), lhs.y() - rhs.y(),
        lhs.width(), lhs.height());
}

inline RectF operator+(const Vector2dF& lhs, const RectF& rhs)
{
    return rhs + lhs;
}

GFX_EXPORT RectF IntersectRects(const RectF& a, const RectF& b);
GFX_EXPORT RectF UnionRects(const RectF& a, const RectF& b);
GFX_EXPORT RectF SubtractRects(const RectF& a, const RectF& b);

inline RectF ScaleRect(const RectF& r, float x_scale, float y_scale)
{
    return RectF(r.x() * x_scale, r.y() * y_scale,
        r.width() * x_scale, r.height() * y_scale);
}

inline RectF ScaleRect(const RectF& r, float scale)
{
    return ScaleRect(r, scale, scale);
}

// Constructs a rectangle with |p1| and |p2| as opposite corners.
//
// This could also be thought of as "the smallest rect that contains both
// points", except that we consider points on the right/bottom edges of the
// rect to be outside the rect.  So technically one or both points will not be
// contained within the rect, because they will appear on one of these edges.
GFX_EXPORT RectF BoundingRect(const PointF& p1, const PointF& p2);

// This is declared here for use in gtest-based unit tests but is defined in
// the gfx_test_support target. Depend on that to use this in your unit test.
// This should not be used in production code - call ToString() instead.
void PrintTo(const RectF& rect, ::std::ostream* os);

} // namespace gfx

#endif // UI_GFX_GEOMETRY_RECT_F_H_
